class A{
  int m;
  int getM(){
    return m;
  }
  int seeM(){
    return m;
  }
}

class B extends A{
  int m;
  int getM(){
    return m+100;
  }
}

public class xiti5_4{
  public static void main(String args[]) {
    B b = new B();
    b.m = 20;
    System.out.println(b.getM());
    A a = b;
    a.m = -100;
    System.out.println(a.getM());
    System.out.println(b.seeM());
  }
}
